If you can run memtest86+ successfully, I doubt that the motherboard is at fault.
Possibly, you need a bios update to handle some unique situation.
I assume your game is up to current patch level and your graphics drivers are up to date.
One possibility is that your psu is weak or failing. Such a condition can cause a problem when under higher graphics load.
What make/model is your psu?
What cpu and graphics cards?